The invention relates to apparatus for removing a sealing plug from a bore.
A sealing plug is usually initially installed in a bore with the intention of remaining installed permanently. However it is sometimes necessary to remove such a sealing plug e.g. for the purpose of maintenance or repair of the equipment in which it is installed. The present invention relates to apparatus for removing a sealing plug. More particularly, the invention relates to apparatus for removing a sealing plug of the type which comprises an outer sleeve and an inner stem retained within the outer sleeve. For example, one such plug is that commercially available under the Registered Trade Mark AVSEAL.
The closest prior art of which the Applicants are aware is GB 2 319 200 A, which is discussed later.
The invention provides, in one of its aspects, an apparatus for removing a sealing plug from a bore, which sealing plug comprises an outer sleeve and an inner stem retained within the outer sleeve, the removal taking place after a suitable hole has been drilled part of the way into the stem, which removal apparatus comprises: a tapered punch for forcible insertion into the hole in the stem thereby to create an interference fit between the punch and the stem and thereafter driving the stem out of the sleeve whilst also retaining the stem on the punch by virtue of the interference fit; and sleeve-engaging means engagable with the sleeve after the punch has removed the stem from the sleeve; the sleeve-engaging means and the punch being thereafter removeable from the bore thereby to remove both the sleeve and the stem from the bore whilst the sleeve and the stem are both retained on the appropriate parts of the apparatus.